陕西杨凌蛋鸡场禽戊型肝炎病毒流行情况调查

发布时间：2018-03-18 04:02

本文选题：禽戊型肝炎病毒　切入点：ELISA检测　出处：《西北农林科技大学》2016年硕士论文　论文类型：学位论文

【摘要】：禽戊型肝炎病毒(Hepatitis E virus,HEV)是鸡的大肝大脾(Big liver and spleen disease,BLS)病或肝炎脾大(Hepatitis-Splenomegaly,HS)综合症的主要病原。该病主要引起30-72周龄的蛋鸡和肉种鸡的死淘率升高(1%-4%)和产蛋率下降(20%-40%),发病鸡通常腹部充血,卵巢退化,肝脏脂肪或淀粉样变性,偶有肝脾肿大。禽HEV感染曾给澳大利亚的养禽业造成了严重的经济损失,而我国也时有该病爆发的报道。2001年禽HEV被首次分离报道,随后许多国家都有该病毒的分离报道。在我国,2010年从患有HS综合征的病鸡中分离得到禽HEV,血清学调查发现该病毒感染已在我国许多蛋鸡场中普遍存在。本研究首先从杨凌的12个蛋鸡场采集了3337份血清,然后利用已建立的禽HEV抗体检测的间接ELISA方法检测血清中的抗体。ELISA检测结果发现1668份血清为禽HEV抗体阳性,阳性率为49.85%。随后,依据2014-2015年陕西杨凌地区部分商品蛋鸡场出现产蛋量下降(10%-40%),剖检部分鸡只发现肝脏肿大出血,疑似为禽HEV感染引起。随后为确诊该疫情的病因,本研究从发病的6个蛋鸡场采集了268份粪便,利用巢式RT-PCR对粪便中的禽HEV RNA进行了实验室检测。巢式RT-PCR检测结果发现63份粪便为禽HEV RNA基因片段阳性,阳性率为23.51%。基因片段的序列同源性分析发现,杨凌地区的禽HEV分离株与国内的同源性为93.0-99.2%;进化树分析表明,其与国内其它地区的分离株在同一进化分支上,同属禽HEV基因3型。
[Abstract]:Avian hepatitis e virus (HEV) is the main pathogen of the disease of the large liver and spleen disease of chickens or the hepatitis spleen Hepatitis-Splenomegalyus HSV syndrome. The disease mainly causes the increase of the death rate of 30-72 week old laying hens and broilers by 1-4) and the decrease of laying rate by 20% -40%, which is the main cause of disease, and the disease is the main cause of the disease, which causes the death rate of 30-72 week old laying hens and broilers to increase by 1-4) and the laying rate decreases by 20-40th. Chickens are usually congested in the abdomen, Ovarian degeneration, liver fat or amyloid degeneration, occasionally hepatosplenomegaly. Avian HEV infection has caused serious economic losses to the poultry industry in Australia, and outbreaks of the disease have been reported in China. In 2001, avian HEV was first isolated. In 2010, avian HEV was isolated from sick chickens with HS syndrome in China. Serological investigation showed that the virus infection has been widespread in many laying chicken farms in China. First, 3337 serum samples were collected from Yang Ling's 12 laying chicken farms. Then the indirect ELISA method for detection of avian HEV antibodies was used to detect antibodies in sera. Elisa results showed that 1 668 sera were positive for avian HEV antibodies, and the positive rate was 49.85%. According to the number of layers in some commercial laying farms in Yang Ling area of Shaanxi Province from 2014-2015 to 2014-2015, the amount of laying decreased by 10-40g. Some chickens were dissected and found liver swelling and bleeding, suspected to be caused by avian HEV infection. Subsequently, the etiology of the epidemic was confirmed. In this study, 268 feces were collected from 6 laying hens, and HEV RNA in feces was detected by nested RT-PCR. The results of nested RT-PCR analysis showed that 63 feces were positive for HEV RNA gene fragment. The positive rate was 23.51.The sequence homology analysis of the gene fragment showed that the homology of avian HEV isolates in Yang Ling area was 93.0-99.2, and the phylogenetic tree analysis showed that the isolates belonged to the same evolutionary branch of avian HEV gene as other isolates in China.
【学位授予单位】：西北农林科技大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：S858.31

【参考文献】